A modest suggestion

let's say that some news agency reports that a certain number of innocent arabs ( to take a random ethnicity) has been killed in a military action and it turns out that it wasn't actually so. That in real life a smaller number of armed thugs got killed along with a yet a smaller number of human shields .
So how do you prevent said news agency from rushing to publish the lies without bothering with such a small detail as the truth?
Simple , You make up the difference between the reported number of people killed and the real number of dead by killing the staff of that news agency starting with the local rep and moving up the food chain .That way either they report the facts or they become part of the report.